Forty-four people were killed when gunmen opened fire at an engagement party in south-eastern Turkey last night in what is believed to have been the culmination of a blood feud between rival families.

Ahmet Ferhat Ozen, the acting governor of Mardin province, told Reuters the masked assailants stormed a hall in the village of Bilge, attacking guests with automatic rifles and hand grenades.

The prospective bride, Sevgi Celebi, and groom, Habib Ari, were killed in the assault – thought to have lasted for 15 minutes – as was the cleric conducting the "introduction" ceremony.

Six children and 16 women were among the victims. One schoolboy survived after the body of his brother, who was killed, fell on top of him.

Earlier reports had said the attack was made on a wedding party.

The Turkish interior minister, Besir Atalay, said the most likely cause of the attack was a feud between families.

"Evidence so far shows it was not the work of a terrorist group," he said when asked whether the militant Kurdistan Workers party (PKK) could have been responsible.

Eight suspects had been detained, Atalay said. Most of them shared the same family name as many of the dead, bolstering suggestions that the attack had been driven by an intra-clan vendetta.

A local official told Turkey's Haberturk TV channel that the killings had arisen from an old feud in a pro-government militia that included the families of the prospective bride – the daughter of the village muhtar, or chief – and groom.

One of the families had reportedly opposed the marriage. The muhtar, Hamit Celebi, was killed along with 10 of his relatives, the state-run Anatolian news agency reported.

Mehmet Besir Ayanoglu, the local mayor, told Turkey's Channel 24 that he had spoken to two survivors of the attack, both girls. "They raided the house ... we were in two rooms – they opened fire on everyone, they were wearing masks," Ayanoglu quoted them as saying.

The survivors said they lay under the bodies of friends until the attack was over.

There were conflicting accounts of how the attack was carried out. Some eyewitnesses said the gunmen had ordered the guests to kneel after herding them into a room, while others said it happened while people were praying.

"There were a few people – they broke into the house and started spraying the place with bullets, hitting both men and women. Their faces were covered with masks," said one 20-year-old woman, who declined to be named.

The woman said around 200 people had been attending the engagement party.

Local media said the families of both the bride and the groom included members of the state-sponsored Village Guard militia, which was set up to combat Kurdish separatist guerrillas in the area. Turkish soldiers and pro-government village guards have been fighting Kurdish guerrillas in the region for years.

Ozen said many people had been wounded, warning that the number of dead could rise. He said paramilitary police had been sent to the village to hunt down the attackers. The Cihan news agency reported that the injured were taken to hospital in Mardin, where they were visited by the city's chief of police.

Ahmet Can, a relative who took the body of his nephew to a hospital, told Channel 24 that the scene of the attack was horrifying. "You could not believe your eyes," he said.

State television said soldiers surrounded the village and cut all roads leading to it. It said there was no power in the village, which could not be reached by telephone. The hunt for the assailants had also been hampered by a sandstorm, officials said.

Blood feuds are not unknown in south-eastern Turkey, but the death toll from the latest incident is likely to lead to pressure on the government to crack down on militias.

Critics say such groups have been responsible for numerous violent acts and accuse them of using their armed status to settle scores and seize land. They are also said to have become involved in drug rings.

However, they are among the few sources of lucrative employment in an impoverished region in which male joblessness in some areas reaches 50%.

PKK rebels have been fighting Turkish forces in the south-east of the country in the battle for a Kurdish homeland since 1984. About 40,000 people, mostly Kurds, have been killed in the conflict.

Last week, Turkey suffered its worst outbreak of political violence in months when nine soldiers died in an explosion blamed on Kurdish militants and a female suicide bomber tried to assassinate a former government minister.